Nearly half of all dementia cases may be connected to health risks people can potentially change — and a new four-year brain study shows exactly how those risks leave their mark on the brain.
What the researchers did
A team at Lund University in Sweden, led by Sebastian Palmqvist, a senior lecturer in neurology and senior physician at the Memory Clinic at Skåne University Hospital, followed almost 500 participants with an average age of 65. None showed signs of cognitive impairment at the start. Over four years, researchers tracked changes in the brain's white matter — the nerve fibers often damaged in vascular dementia — and measured levels of amyloid β and tau, the two proteins most associated with Alzheimer's disease.
Their aim was to separate the effects of risk factors a person cannot change (age, gender, genetics) from those they can (smoking, cardiovascular disease, high blood lipids, physical activity, alcohol consumption, hearing loss, and high blood pressure).
What they found
Most modifiable risk factors — smoking, cardiovascular disease, high blood lipids, and high blood pressure — were linked to damage in the brain's blood vessels and a faster buildup of white matter changes. As doctoral student and neurology resident Isabelle Glans explained, this damage impairs blood vessel function and leads to vascular brain damage, which can ultimately lead to vascular dementia.
The team also spotted possible connections to Alzheimer's proteins: diabetes was associated with increased amyloid β accumulation, while people with lower BMI showed faster tau accumulation. Glans cautioned that these specific findings need further investigation and validation in future studies.
Why it matters for your brain
Dementia is not one disease but a collection of symptoms with different underlying causes — which is why earlier research that lumped all risk factors together offered limited insight. This study is notable because it tracked individual risk factors against specific brain changes over time.
The practical implication is important: many people with dementia have more than one disease process happening in the brain at once, including both vascular damage and Alzheimer's-related changes. Palmqvist noted that improving vascular and metabolic health may therefore remain valuable even for people already at risk of Alzheimer's disease, because it can reduce the combined effects of several brain changes occurring simultaneously.
What you can do
- Keep blood pressure and cholesterol in a healthy range — both were directly tied to white matter damage.
- Avoid smoking; it appeared among the strongest vascular risk factors.
- Manage blood sugar, since diabetes was linked to amyloid β buildup.
- Stay physically active and moderate alcohol intake — both are on the modifiable list.
- Address hearing loss, another factor the study identifies as changeable.
These steps are not a guarantee against dementia, but they target several harmful brain changes at once — a strategy that may help delay symptoms.
Source: ScienceDaily Mind & Brain
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